properties of some mysterious entelechy associated with that system; they are non-deducible properties of the
system itself. Broad's emergence is a form of nonreductive supervenience, since his emergent properties are
completely determined by and dependent upon lower-level physical and relational properties, though the emergent
properties cannot be defined in terms of the lower-level properties of the constitutive entities.
On Broad's account, emergence theories also explain each emergent property. These explanations are provided by
the structures of the wholes that give rise to emergent properties. Broad says that
[A non-vitalistic theory] "tries to explain the difference of behavior wholly in terms of difference of
structure." On the first form of the theory the characteristic behavior of the whole could not, even in theory,
be deduced from the most complete knowledge of the behavior of its components, taken separately or in
other combinations, and of their proportions and arrangements in this whole. This alternative, which I have
roughly outlined and shall soon discuss in detail, is what I understand by the "Theory of Emergence."
(Broad 1925 p. 59)
Broad denies that such explanations lead to reduction on the grounds that emergent properties are those for which
there are no general laws relating the properties of wholes to properties of their constituents (Broad 1925 pp. 64-65).
Broad's view is that emergent properties can only be explained by examining the structures of the wholes in which
they appear; nothing can be learned about emergent properties by studying the constituents of those wholes in
isolation or by studying other wholes in which those constituents appear.
At this point some examples may help to explain the concept of emergence. In 1925, Broad felt that the property of
being alive was a candidate for emergence since it was not apparently reducible to a mechanistic property of matter,
and yet he thought that it could be explained in terms of the structure of particular living bodies without appeal to
vital essences. Broad also suggested that liquidity and subjective mental properties (e.g. the characteristic odor of a
chemical compound) were candidate emergent properties. Liquidity is now not a candidate emergent property
because scientific advances have explained it in terms of mean molecular kinetic energy and the strength of intermolecular attraction; I will argue that mental properties are emergent below. Some clearly non-emergent properties
include the property of weighing 10 lbs, and having a particular physical shape. These properties can be easily
derived from our knowledge of the weight and bonding properties of the atoms that make up any particular object.
These two properties meet Broad's rough holistic criterion mentioned above, but they don't meet his more specific
definition of emergence.
Emergence can be characterized in terms of three features of Broad's account: nonreduction, supervenience, and
structural or holistic explanation. A theory containing emergent properties or entities is not reducible to lower-level
theories. At the same time, a theory of emergent properties does not postulate anything that is not ontologically
justified by the lower-level theories. Finally, the theory allows us to explain all the properties or entities required by
the theory in an acceptable way. However, Broad's account of emergence can be improved. A stronger account of
emergence will avoid the charges of epistemological relativism that were made against Broad's theory. A stronger
account of emergence will also show how it is possible for structural explanations of emergent properties of wholes
to exist while there are no general laws relating emergent properties of wholes to properties of the constituents of
those wholes. I argue below that a definition of emergence following Broad but using contemporary analyses of
supervenience, reduction, and explanation is sufficient to solve the mind-body problem.
Solving the Mind-Body Problem
The mind-body problem arises when we attempt to reconcile two theses about the world. The first thesis is that of
materialism: everything that exists in the universe is a material or physical thing, reduces to material or physical
things, or supervenes on material or physical things. The second thesis is what I will call mentalism: there are things
that have mental properties. In the second thesis, the word 'mental' is normally intended to apply to such things as
emotions, sensations, and thoughts. For a materialist, reconciling these two theses consists in explaining mental
properties in physical terms. Such explanations are difficult because mental properties have a special character that
seems to foil any attempt at explaining them in physical terms. Davidson explains the special character of the mental
by appeal to what he calls the anomalousness of the mental (Davidson 1970). For Davidson, the mental is
anomalous because there are no laws relating the mental to the physical in spite of the fact that the mental is
dependent upon the physical. Nagel explains the special character of the mental by appeal to the subjectivity of the
mental (Nagel 1974). For Nagel, the mental is intrinsically first-person or subjective and it cannot be explained in
physical terms since such explanations must be made from a third-person or objective point of view. A materialistic
solution to the mind-body problem must thus somehow explain the mental in physical terms while simultaneously
respecting the special character of the mental.
Most theories of the mind fail to meet these desiderata. Dualistic theories, whether substance dualism or property
dualism, fail to explain mental properties in physical terms. It is, in fact, impossible for dualism to provide such an
explanation since dualism requires that the mental and the physical be fundamentally different. Behaviorism and
type-identity theories also fail to provide an account of the special character of the mental. These theories try to
reduce the mental to the physical in a way that does not allow the mental to have a special character. Reductive
accounts must explain the mental as simply another physical property without any particular distinguishing
characteristics, otherwise the reduction cannot go through. Thus, straightforward versions of materialism or
mentalism cannot meet both of the desiderata above because they emphasize only one of them, or only one of the
two theses that must be reconciled.
Computational functionalism also fails to meet the desiderata proposed above. Ned Block has argued that
computational functionalism is unacceptable because it does not accurately characterize the class of sentient
creatures (Block 1978). For Block, some clearly non-sentient entities can meet the functional specification of a
sentient entity without having any mental properties. For example, Block argues that the people of China, if suitably
organized and instructed, could implement the computational-functional characterization of a mind. However, Block
suggests that there will be no qualia in such a situation. Thus, some crucial mental properties are left out of the
functional description. In short, while it is possible for something that meets the functional specification of a sentient
being to have a mind, it isn't necessary. Thus, the functional account of the mind isn't sufficiently explanatory.
Pure supervenience theories are also insufficiently explanatory. Pure supervenience theories say that the mental must
depend upon and be determined by the physical (Kim 1982). However, they add little or nothing to this basic claim.
While this allows for special mental properties, it doesn't say how they arise, or give any account of why they are
special. Thus, neither computational functionalism nor pure supervenience are acceptable solutions to the mind-body
In contrast, an emergence theory can meet the desiderata due to the three properties characteristic of emergence.
Because emergence is a kind of supervenience that supports explanation, emergence theories of the mental can
explain the mental in physical terms. Because emergence is nonreductive, it allows for mental properties that have a
special character different from standard physical properties (which are reductive). The nonreductive character of
emergence is consistent with both Davidson's and Nagel's characterization of the special character of the mental -- it
allows us to explain the subjectivity and anomalousness of the mental without contradiction. Since an emergence
theory of the mental requires that mental properties be irreducible, there will be no laws relating mental properties
and physical properties, and there will be no third-person objective descriptions of mental properties in physical
terms. Thus, an emergence theorist holds that both Davidson and Nagel are correct in suggesting that the mental has
a special character, but denies that this character puts the mental completely beyond the reach of any materialistic
explanation. This is the strength of emergence theories: they can incorporate properties of a special character while
requiring that those properties supervene on the material world in a way that allows for acceptable explanations.
So far, I have presented only the most general kind of reason to think that an emergence theory can solve the mindbody problem. There are two main obstacles at this point. First, one may ask if the concept of emergence is
coherent. That is, one may ask if it is possible to concoct an emergence theory without contradiction or other
undesirable consequences. Second, one may wonder if there is any reason to think that emergent mental properties
actually exist. In the remainder of the paper, I present a precise account of emergence, I suggest how such an
account can be used to explain mental properties, I argue against Kim's suggestion that downward causation is a
problem for any theory of emergence, and I argue that the theory of emergence presented below is superior to
O'Connor's theory of emergence.
The following definition of emergence is a modification and modernization of Broad's less precise account. Like
Broad's definition, this definition expresses the idea that emergence is a variety of nonreductive supervenience, and
it requires an explanation-supporting relation between emergent properties and their supervenience base. The
explanation-supporting relation must be weak enough that reduction is not required. For this reason, nomologicaldeductive models of explanation are ruled out since they are so closely related to traditional accounts of reduction.
The definition also avoids the chief problems with Broad's account. The first problem was that Broad's concept was
interpreted to be epistemically relative. This is avoided by requiring that any theories discussed in the definition be
ideal theories (i.e. theories that get everything right -- the best possible theories). Following Broad, the definition is
cast in epistemological terms, but this does not imply that emergence is a strictly epistemological relation. Like
many epistemological approaches to reduction, the definition is intended to characterize a metaphysical relationship.
Requiring ideal theories in the definition helps here also, since ideal theories are clearly a definitional tool rather
than a characterization of any particular epistemic situation. The second problem was that Broad's theory allowed
for structural explanations of emergent properties, which some theories of explanation might suggest are
incompatible with the non-reductive nature of these properties. Thus, the definition requires that emergent properties
be nonstructural or not completely structural. The definition expresses each of the main concepts of supervenience,
nonreduction, and explanation in a separate clause:
A property designated by a predicate P in an ideal theory T is emergent if and only if the following
conditions are met:
T describes a class of systems SC which are structured aggregates of entities described by T'; T' is
an ideal theory of those entities, and the entities described by T strongly supervene on those
described by T'.
It is epistemically impossible to identify occurrences of the property designated by P with any
occurrence of a property finitely definable in T'.
Each occurrence of the property designated by P is an occurrence of one of a definable set of
properties PC, which is modeled by T'. Each member of PC is epistemically indistinguishable in T'
from some other member of PC. (Newman 1995, 1996)
Some further explanation of the definition may be helpful. The first clause of the definition requires the kind of
structured wholes that Broad discusses in the quotation provided earlier. It also requires strong supervenience as
defined by Kim (Kim 1987). However, the particular form of supervenience is not crucial to what follows. I believe
that Horgan's regional supervenience would work just as well (Horgan 1993). The second clause guarantees
nonreducibility by preventing the definition of the emergent properties in terms of a lower-level theory. The idea
here is that the emergent properties have some metaphysically special character that prevents their definition. This
should also prevent emergent properties from being purely structural since structural properties are relational
properties that can presumably be defined in physical terms. I have phrased the restriction in terms of epistemic
impossibility because it must not contradict the first clause. However, the epistemic impossibility of the identities
must be universal in order to avoid the charges of epistemic relativism levelled against Broad: it must be impossible
to formulate the identities in any epistemic situation. I have used the notion of finite definability because I believe
that any physical property can be characterized using an infinite disjunction describing each of its instances, and I
want to rule out this kind of characterization as a possible reductive definition. The third clause guarantees the
existence of some form of model-based explanation. If emergent properties are members of a larger class of
properties which can be defined even when the particular members of the class cannot be defined, then explanations
of those properties can proceed in terms of the features that all members of the class share. In other words, an
emergent property will be explicable by virtue of some general characterization of that property that is not
sufficiently precise to qualify as a reductive definition. The definition of emergence given above will be applied to a
concrete example below.
There are two ways that the proposed definition might be incoherent: it might be internally contradictory, or it might
not be distinct from pure supervenience, reduction, or dualism. First, consider the possibility that the definition is
incoherent. If explanation or supervenience require reduction, then the definition would be internally inconsistent.
Since contemporary models of explanation don't require reduction, it seems safe to assume that explanation and
nonreduction are mutually consistent. Since supervenience is a more general concept than reduction (i.e. instances of
reduction are instances of supervenience) they must be mutually consistent. Finally, since supervenience says
nothing about explanation, and is a very general thesis, it too seems consistent with the existence of an explanation
for supervenient properties. Thus, it seems a reasonable working hypothesis that the definition is internally
consistent. Now consider the possibility that the definition is not distinct from pure supervenience, reductive
materialism, or dualism. First, the relation defined is distinct from supervenience because the third clause is strictly
stronger than supervenience. Second, if clause (2) successfully rules out reduction, emergence as defined here must
be distinct from reduction. It seems clear that reduction is ruled out since reduction relies on bridge principles
between higher and lower-level theories, and the second clause effectively prohibits the formulation of such
principles by ruling out any instances of such principles. If supervenience rules out dualism, then the inclusion of the
first clause guarantees that the definition is distinct from dualism. Thus, the definition appears to be suitable subject
to the worry that it might not have any instances in the universe and that it might not apply to mental states; these
worries will be dealt with in the following two sections.
To prepare the way for the arguments to follow, a brief discussion of chaotic nonlinear dynamical systems (hereafter
CNDSs) is in order. I will briefly review here some important features of the class of CNDSs that are also
dissipative systems. Roughly speaking, dissipative systems are systems that consume energy. There are chaotic
systems that are not dissipative, but these do not play a role in my argument. I will also briefly review an argument I
have given elsewhere that CNDSs have emergent properties. Finally, I will briefly present the evidence that human
brains are chaotic systems.
CNDSs cannot be analyzed using the mathematical models and techniques that have dominated most scientific
research. They exhibit apparently random behavior, which is part of the reason they are so difficult to model.
However, they can be analyzed using a set of techniques sometimes called dynamical systems theory. Any
dynamical system can be described by some number of variables; the abstract space constructed from the possible
values of these variables is called the phase space of the system (this is also sometimes called a state space). The
behavior of a system can be described as a set of trajectories within its phase space in the sense that when the system
is started in any particular state, its dynamical evolution will result in a sequence of states that form a trajectory in
the phase space. The trajectories in the phase space of a dynamical system typically converge on one or more
regions in the phase space; these regions are called attractors, and the region of the phase space in which all
trajectories converge on a particular attractor is called the basin of attraction of that attractor. Dynamical systems
can be classified according to the topological properties of their attractors. The dynamical systems approach allows
us to classify all dynamical systems using four patterns of behavior.
The first three kinds of behavior are associated with systems that can be analysed using traditional mathematical
methods. If all the trajectories of a system converge on a single point, the system is said to have a point attractor. An
example of such a system would be a simple pendulum with friction. Regardless of the speed or angle at which the
pendulum is swung, it will always slow down and stop, hanging vertically. If all the trajectories of a system
converge on a loop in the phase space, the system is said to have a limit cycle. An example of this kind of system is
a driven pendulum with friction. Regardless of the speed or angle at which the pendulum is swung, it will eventually
come to swing at a fixed frequency determined by the length of the pendulum, the weight of the bob, and the
magnitude and frequency of the driving force. If all the trajectories of a system converge on a torus shape in such a
way that there is no limit cycle, then the system is said to be quasiperiodic. An example of this kind of system is a
pair of driven pendulums with incommensurable frequencies (i.e. the frequencies make an irrational ratio). The
frequency of one pendulum controls the interval in which the system proceeds around the hole in the torus, and the
frequency of the second pendulum controls the interval in which the system proceeds around the smaller crosssection of the limb of the torus. Because the two frequencies are incommensurable, the attractor of such a system
wraps densely around the torus, but is not periodic. Systems with one of these three kinds of attractor are easily
understood using traditional mathematical models and analytic techniques.
CNDSs exhibit behavior different from each of the three classes of systems introduced above. The trajectories of a
CNDS converge on a highly complicated shape that is typically a fractal (i.e. it has non-integer dimension). This
shape is a topologically closed set of non-periodic trajectories, and it is characteristically a set of closely packed
highly similar trajectories something like a filo pastry. An example of a CNDS is a driven hinged pendulum. The
behavior of this kind of system is highly sensitive to the initial speed and angle at which it is swung, and such a
system will behave in a seemingly random fashion. The apparent randomness in the behavior of a CNDS arises
because CNDSs have sensitive dependence on initial conditions. This is sometimes called the 'butterfly effect'. This
means that very small perturbations of the state of a CNDS will have relatively large effects on its behavior
(typically the effects are an exponential function of the perturbation, while non-chaotic systems may respond to
perturbations in a linear or non-exponential way). The attractors that describe the behavior of CNDSs are known as
Using the property of sensitive dependence on initial conditions, it is possible to show that CNDSs have emergent
properties. In some CNDSs, perturbations so small as to be immeasurable can have effects on the behavior of the
system that are so large as to invalidate any possible prediction of the course of a CNDS' behavior (Kellert 1993).
Because we can only measure the state of a system with finite precision, and because any error in our measurement
is magnified in an extreme way by a CNDS' sensitive dependence on initial conditions, there is a sense in which it is
impossible to define the states of some CNDSs. For the same reason, it is impossible to define (or measure) the
strange attractor of such a CNDS. However, if we understand the dynamics of a CNDS, we can determine an
equivalence class of strange attractors within which its behavior will fall. For this reason, being in the basin of
attraction of a strange attractor is an emergent property of a CNDS. This property supervenes on the physical state of
the CNDS, so clause (1) of the definition above is met. Because the states and attractors of the system cannot be
defined, it is impossible to reduce the basin of attraction to physical terms, and clause (2) of the definition is met.
Finally, because the behavior of the system can be explained in virtue of the equivalence class of strange attractors,
clause (3) of the definition is met. Thus, there are physical systems that have emergent properties, and one of the
remaining worries regarding emergence is eliminated.
The arguments below regarding the emergence of mental properties depend on the fact that the brain is a CNDS.
There are two basic reasons to think that this is the case: the first is empirical, the second is theoretical. Empirically
speaking, there are two sets of results that suggest the brain is a CNDS. First, there are a number of studies that find
strange attractors in human EEG recordings (Basar 1990). Second, Skarda and Freeman have found that rabbit
olfactory systems exhibit different strange attractors when presented with different odors (Skarda and Freeman
1990). This suggests that all mammalian neural systems are CNDSs, and thus that human brains are CNDSs.
Theoretically speaking, the brain is just the kind of nonlinear dynamical system that typically has chaotic dynamics.
The constituent neurons and synapses of the brain exhibit nonlinear behavior, and they are connected together in
such a way that sensitive dependence on initial conditions will result at a higher level (Foss 1992). Thus, although
further empirical work remains to be done, it seems very likely that human brains are CNDSs.
It is now possible to consider the possibility that mental properties are emergent. If being in a mental state is
analysed in terms of being in the basin of attraction of a strange attractor of the brain, then mental states are
emergent because the basins of attraction of the strange attractors of any CNDS are emergent, as discussed above.
The mental states I am concerned with here are the occurrent mental states. These are the states that are most closely
associated with consciousness, subjectivity, and the mind-body problem as characterized by Nagel et. al. They are
the states that are most difficult to explain, and they are the states that the emergence account is intended to handle.
They include sensations, emotions, and having a thought, and they are typically defined in terms of their content. I
argue here that we should understand these states in terms of strange attractors because our folk psychological
understanding of these states requires that they be analyzed in terms of the basins of attraction of strange attractors
rather than the basins of attraction of point attractors, limit cycle attractors, or torus attractors.
There are a number of features of occurrent mental states that are easily noted, and which can be used to show that
mental states should be associated with strange attractors. The first thing to notice about occurrent mental states is
that they are part of a dynamical system, and that they are extended in time (Morton 1988). Mental states are part of
an 'ecology' of the mind in which states come and go, and in which states and their relations to each other change as
time passes. For example, if one is angry, one can also be hungry, and the hunger can come and go while the anger
remains. Further, the state of anger itself may evolve over time, becoming (e.g.) less extreme as the source recedes
in time, or changing as one considers different methods of exacting one's revenge. Thus, mental states have duration
and are not completely uniform through that duration. In addition, mental states are not noticeably rhythmic: they do
not have reoccurring features that occur at regular time intervals. Finally, mental states are neither predictable nor
strictly random; no one can precisely predict the sequence, duration, or quality of our mental states, yet our mental
states are not normally so random that they are surprising or shocking. Because the mind is plausibly constituted of a
number of dynamical systems (e.g. the vision subsystem and the language subsystem), it is reasonable to ask about
the attractors of these systems. By doing this, we will be able to show that mental states are plausibly considered to
be emergent properties.
The folk psychological properties of mental states examined above make it plausible that mental states should not be
modeled by point attractors, limit cycles or torii. Because mental states evolve through time, and because they show
no tendency to stay in a particular state for any extended period of time, it seems clear that the mind does not have
point attractors within its phase space. Since mental states show no evidence of periodicity, we can also eliminate
limit cycles from the possible features of the phase space of the mind. For the same reason, we can eliminate torii
since the mind would exhibit periodicity with respect to a particular set of features (though not with respect to its
total state) if there were torii in its phase space. Thus, by elimination, mental states should be modeled by strange
attractors. There are also positive reasons to think that mental states are like strange attractors. For example, the
seeming randomness of behavior characterized by a strange attractor may be likened to the unpredictability of
human nature, and the sensitivity of human mental states to very small stimuli may be indicative of sensitive
dependence on initial conditions. Finally, Skarda and Freeman's result concerning rabbit olfactory systems is very
suggestive (Skarda and Freeman 1990). Since rabbits' brains exhibit different strange attractors when presented with
different odors, and since experiencing a smell is a typical mental state of the kind that we seek to explain, it seems
reasonable to conclude that rabbit mental states are associated with strange attractors. From this conclusion, it is a
small leap to suppose that other mammals, including humans, have mental states similar to rabbits' mental states.
Thus, when the mind is treated as a dynamical system, mental states should be modeled using the basins of attraction
of strange attractors, and they are thus emergent by the argument above that being in the basin of attraction of a
strange attractor is an emergent property of any chaotic system.
On this account, mental states are defined in terms of classes of similar strange attractors of brain subsystems. More
precisely, being in a mental state is being in the basin of attraction of a strange attractor of some subsystem of the
brain. Mental states are thus constituted by the basins of attraction of all members of a class of similar strange
attractors in the phase space of the brain. This is not a reductive account since our inability to measure the brain with
precision sufficient to overcome its sensitive dependence on initial conditions prevents us from defining any
instance of a mental state in physical terms. In other words, we cannot identify mental state occurrences with the
basin of attraction of particular strange attractors. Because we regard mental states as the basins of attraction of
classes of strange attractors, this view is a kind of functionalism (broadly construed). Using a class of similar strange
attractors to define a mental state is a functional definition of a mental state, since any physical state that instantiates
the causal dynamics of the strange attractors in the class is a mental state of the corresponding kind. Unlike
computational functionalism, the emergence account has a story to tell about the special character of mental states.
Like computational functionalism, the emergence account suggests that mental states are multiply realizable.
Further, because mental states are described by a class of strange attractors that all have similar features, we can
explain the general features of those mental states even though we cannot identify them precisely. The level of
precision available here seems to be about the level of precision afforded by folk psychology. If an account of
mental states in terms of classes of strange attractors can explain the predictive successes and failures of folk
psychology, then this is another reason to think that it is plausible.
The key question, however, is whether or not the theory advanced here can solve Chalmers' hard problem. Can this
theory bridge the explanatory gap? For two reasons, I believe that it can. First, the emergence theory postulates the
existence of special physical properties fundamentally different from other physical properties. Since the emergent
properties with which I analyze mental properties are supervenient on the physical, they are firmly grounded in
accepted metaphysical entities. Since they are not reducible to the physical, emergent mental properties are
fundamentally different from traditional physical properties like those considered in reductive or functional
approaches to the mind-body problem. These two features suggests the foundations or footings of the desired bridge
between the physical and the mental. The bridge itself is the holistic explanation of groups of emergent properties in
terms of their supervenience base. The difficulty of constructing the bridge lies in the fact that individual emergent
properties cannot be explained. This failure of individual explanation comes about because mental properties are
fundamentally non-reductive and hence anomalous: mental properties are not finitely definable and they
consequently cannot participate in any finitely expressible laws or explanations. Thus, if emergent properties are
plausibly identifiable with mental properties the emergence theory relates the mental and the physical in a way that
explains why the mind-body problem is so difficult. The emergence theory thus provides at least a plausible solution
to the mind body problem. However, some will still be unsatisfied for the reason that the explanation given so far
does not address the question of qualia.
The second reason I think that the emergence theory can bridge the explanatory gap is that I believe the emergence
theory can explain some of the interesting features of qualia. Emergent properties are plausibly identifiable with
mental properties if we consider the properties shared by all qualia rather than those of particular qualia. This
procedure is required because the theory presented here suggests that no individual mental state can be explained.
This comes about because the individual mental states cannot be adequately identified since they are states of
chaotic systems, which have the property of sensitive dependence on initial conditions. In particular, if mental states
are not finitely describable we can explain Nagel's 'what it is like' and Guzeldere's further-how question. Mental
states that are not finitely definable would be inherently private since it would be impossible to make measurements
precisely enough to distinguish one mental state from another similar mental state. Similarly, any definition
proposed for something that is not finitely definable would be incomplete, allowing a further-how question to be
asked. Thus, the emergence theory agrees with the other investigators who have suggested that the subjective quality
of mental states is inexplicable. However, the emergence theory offers an explanation for why this is the case, and
still provides a materialistic foundation for those mental states and their unusual properties.
The emergence theory also allows for some explanation of other qualities of experience as described by William
James using the metaphor of the stream of consciousness (James 1976). James' metaphor suggests that occurrent
mental states have a dynamic kind of flow in which the boundaries between particular mental states are unclear, and
in which the distinctions between different mental states are very subtle. If being in a mental state is being in the
basin of attraction of a strange attractor of a brain subsystem, the subtlety of the boundaries between mental states
and the subtlety of their differences is explained by the fact that the basins of attraction of strange attractors can have
fractal dimension, meaning that their boundaries are so complicated that they cannot be easily characterized.
Furthermore, several such basins of attraction can be tangled together in a complex way, making the differences
between them very small. James' metaphor also suggests that occurrent mental states are inchoate and non-linguistic.
While this can only be true of some mental states, it too is explicable in the theory presented here. Low-level
physical states of the brain, it seems, must be the foundation on which linguistic states are built. For if qualitative
mental states were linguistic, then the problem of expressing what they are like would seem to be less severe than it
is. Thus, qualia are probably non-linguistic, which is explained in the current theory by fact that strange attractors
are non-linguistic. So James' classic description of consciousness and qualia is largely explained by the emergence
The theory presented here has not really explained the features of qualia for which many seek an explanation. Much
work remains to be done, both theoretical and experimental, to make the proposed relation between qualia and
strange attractors more plausible, and to further elucidate the nature of our mental states. However, if the theory
presented here is correct, there will always be unanswered questions about mental states. Indeed, if the theory
presented here is correct, some of these questions will be unanswerable. Thus, it is not a criticism of this account to
suggest merely that it does not provide a complete explanation of mental states. It is my hope that further
investigation will provide more explanation than is given here, but I believe that the foundation laid here is sufficient
to allow a view across the explanatory gap even if no bridge is possible.
Having given a positive argument for the thesis that mental properties should be understood as emergent properties
of the brain. I turn now to Jaegwon Kim's argument that emergence is not a plausible account of the mental. This
argument suggests that any emergence account must accept the existence of downward causation and that this
violates the causal closure of the physical world (Kim 1993). Further, Kim suggests that violation of the causal
closure of the physical world is not to be countenanced by any physicalist. Kim's argument is that unless they are
considered epiphenomenal, mental states must have causal powers. It is certainly plausible that mental states cause
further mental states. However, Kim argues that mental states must also cause physical states since otherwise, there
is causal overdetermination of the subsequent mental states (i.e. from the physical realization of the second mental
state and from the first mental state). Kim suggests that the solution to this problem is to allow that each mental state
causes the physical realization of subsequent mental states to occur, thus also causing the subsequent mental state.
This is why Kim thinks that emergence theorists must accept downward causation. Kim then claims that this violates
the causal closure of the physical since on this account the physical realization of a mental state cannot cause the
physical realization of a subsequent mental state on pain of epiphenomenalism. Thus, says Kim, emergentists cannot
be physicalists since physicalism requires the causal closure of the physical.
The causal closure of the physical is not really violated in this case. The mental state that Kim is worried about is
supervenient on a physical state. All the causal powers of the mental state must supervene on the causal powers of
the physical state. While the causal powers of the mental state are not reducible to those of the physical state, they
do not originate outside the physical world. I would suggest that the causal powers of the mental state are emergent,
making them acceptable to the physicalist in the same way that the mental state itself is acceptable to the physicalist.
Another reason to think that Kim's argument is incorrect is that it applies to functionalism as well as emergence
since it nowhere relies on features of an emergence theory that are not also shared by a functionalist theory. Yet it is
highly plausible that one can consistently be both a functionalist and a physicalist. Thus, contrary to Kim's
suggestion, the causal closure of the physical world is maintained, and emergence theorists can be physicalists.
Before concluding, I would also like to consider a competing account of emergence by Timothy O'Connor
(O'Connor 1994). This account of emergence is formulated in terms of supervenience, non-structuralism, and novel
causal effectiveness. O'Connor understands supervenience in much the same way that I do, so any differences
between my view and O'Connor's will involve differences between his non-structuralism and novel causal
effectiveness conditions on the one hand, and my non-reduction and explanatory conditions on the other. For
O'Connor, nonstructuralism rules out structural properties and properties inherited by a whole from one or more of
its parts. I believe O'Connor thinks non-structural properties of a whole are neither dependent upon any physical
relation that holds between the constituents of a whole, nor a kind of summation of a property over all constituents
of a whole. Nonstructuralism and nonreduction both play similar roles in their respective accounts of emergence, but
the two conditions are quite different. Nonstructuralism seems to be strictly stronger than nonreduction since
nonreduction allows structural properties so long as they cannot be defined, yet it seems impossible for nonstructural
properties to be definable. For O'Connor, novel causal effectiveness is a form of downward causation from the
emergent level to a lower level that brings about effects that would not have occurred if the emergent property had
not been instantiated. This is at least a denial of epiphenomenalism with respect to emergent properties. Novel
causal effectiveness is a very different kind of constraint than the explanatory constraint in the account presented
above. Due to the interactions between the various components of the two accounts, a conceptual comparison is not
straightforward; I will follow O'Connor in comparing the extensions of the defined concepts.
O'Connor criticizes accounts of emergence similar to Broad's on the grounds that they classify some non-emergent
structural properties as emergent. His claim is that any account of emergence based on the idea that emergent
properties cannot be deduced must include within the class of emergent properties causal properties that depend on
the macro-structure of the wholes that have them. He further claims that these causal properties are not emergent
because they are structural properties, and that nondeducibility definitions of emergence are therefore invalid. In
order for this argument to apply to the account presented above, it must be the case that my definition of emergence
cannot rule out all causal properties that depend on the macro-structure of the wholes that have them, and it must be
the case that all such causal properties are not emergent. To show that the account of emergence given above is not
subject to O'Connor's criticism, I must show that one or the other of these claims is false.
Consider the claim that there are causal properties that depend on the macro-structure of the wholes that have them
which meet the definition of emergence presented above. That definition suggests that properties that can be finitely
defined in terms of the properties of the constituents of a whole are not emergent. It thus rules out those causal
properties that depend on the macro-structure of the wholes that have them in a way that is finitely definable.
However, the definition above does not rule out all of O'Connor's worrisome properties since it seems possible that
there are properties that depend on undefinable macro-structural properties. Hence we must consider O'Connor's
second claim. For O'Connor, emergent properties cannot depend on the macro-structure of the wholes that have
them. I suspect that the reason for this is either that such dependence seems to allow us to explain the emergent
property in a reductive fashion, or that such dependence amounts to downward causation. Since we have rejected
downward causation in the discussion of Kim's criticism above, this leaves the possibility of reductive explanation.
However, as we have seem above, dependence may only allow us to make a very general kind of explanation,
particularly when the emergent property is undefinable. Therefore, if emergent properties can be dependent on the
macro-structure of a whole in a way that does not allow detailed explanations, O'Connor's second claim is false, and
his criticism of Broad's account will not apply to the account advanced here.
I believe that the account presented here is superior to O'Connor's for several reasons. First, defining emergence in
terms of indefinability has the useful consequence that we can allow emergent properties that are weakly dependent
on the wholes that have them. This seems right since otherwise we have trouble explaining the emergent properties,
and the supervenience of the emergent properties on their supervenience base becomes mysterious. Second,
properties that meet the third clause of the definition presented above will have novel causal effectiveness (when this
is taken in a way not dependent on downward causation) since these properties will have at least the causal powers
of the larger class of properties of which they are members. Third, O'Connor's definition of emergence depends on
the notion of downward causation, which I believe is troublesome and fraught with difficulty. Fourth, O'Connor's
concept of emergence allows for emergent properties that are inexplicable in a strong sense, and this means that
there will be little practical difference between these properties and truly mysterious properties for which there is no
scientific justification. Fifth, and finally, I believe that definability is a clearer concept than nonstructuralism, and
that it is more useful due to its connections to computability and other concepts. Thus, the choice between
O'Connor's theory of emergence and that presented above rests on the idea that emergent properties can be weakly
dependent on structural (but undefinable) properties of a whole, but I believe that the theory presented here more
closely represents our intuitive notion of emergence.
If the arguments I have presented above are correct, there are a number of important things to notice. First,
emergence is a variety of metaphysical realism with respect to the mental. Emergence accounts do not eliminate the
mental, and yet they suggest that mental properties are metaphysically different from standard reductive physical
properties. Second, emergence is not a form of epiphenomenalism since qualia are information-bearing states of
physical brains that in some sense constitute human mental life. As suggested in the response to Kim, emergent
mental properties have causal powers, and they come by them honestly. Third, emergence provides an opportunity
for a partial explanation of mental states, and thus is superior to functionalism and dualism in this respect. Finally,
the hypothesis is empirically testable. We can perform experiments to determine if human brains are chaotic
systems, and whether or not mental states are correlated with strange attractors in the state space of the brain. All
four of these features are advantages for a theory of the mind.
The emergence account also provides an explanation for the various aliases under which the mind-body problem has
come to be understood. The explanatory gap exists because the accounts we have examined to date do not provide
the kind of positive explanatory structure that emergence does, and because the nature of mental states foils other
explanatory structures. The problem seems hard because we have been looking for reductive or functional accounts
rather than an emergence account. We can ask Guzeldere's further-how question because we have focused on
reductive explanations, blinding ourselves to other possibilities. Thus, since the emergence account has a number of
theoretically advantageous properties, and because it explains the difficulty we have encountered in trying to solve
the problem, there are good reasons to investigate emergence further, both theoretically and empirically.
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(1) My thanks to Nick Asher, Rob Koons, Johanna Seibt, Fred Kronz, Cory Juhl, James Garson, Robert Causey, Jeff
Foss, Pat Manfredi, and the philosophy faculty of Western Michigan University for fruitful discussion of these
issues, or for comments on various versions of this research.
(2) For other recent discussions of the concept of emergence, see (Beckermann, Flohr, & Kim 1992).
(3) I use Broad as the paradigmatic example of an emergence theory because I find Broad's work most similar to my
own way of thinking about emergence. However, Klee (1984) compares different theories of emergence and argues
that those like Broad's are more plausible than other versions of emergence. Klee divides emergence theories into
four groups based on the fundamental characteristic of emergent properties: unpredictability, novelty, variability,
and downward causal effectiveness. Broad's theory and mine characterize emergence in terms of unpredictability or
(4) I mean supervenience in the general sense of (Kim 1984).
(5) In this paper, I rely on a standard understanding of reduction (Causey 1977). Cory Juhl has suggested to me that
it is possible to interpret emergence as a weak kind of reduction. Even if this is possible, I think it confuses things
rather than clarifying them.
(6) See (Nagel 1961 pp. 366-379) and (Hempel 1948 pp. 245-290).
(7) If a structural explanation of a property involves general laws relating that property to the properties of the
entities that constitute the structure, then Broad's program fails. It is thus important to be clear on how it is possible
for emergent properties to be explained in ways that do not require reduction. I hope to discuss this issue at another
(8) Note the similarity between Broad's view and Davidson's. Both suggest that mental properties are not related to
physical ones by any general laws.
(9) Panpsychism meets the desiderata, but (Van Cleve 1990) argues that emergence is a better hypothesis than
panpsychism if the argument for panpsychism is Nagel's. Mental properties are also unexplained under
(10) Of course, models of explanation that do not require objective laws and reductions to physics are required for
the emergence approach to work.
(11) Searle's version of emergence doesn't seem to be distinct from reduction (Searle 1992). Searle himself calls his
view causal reductionism but denies that ontological reduction of the mental is possible.
one in the upper right corner of Figure 1. If a system consists of two pendulums swinging with incommensurable
frequencies, the joint system consisting of both pendulums will have a quasi-periodic attractor (a torus). The phase
space of such a system will require four dimensions, and the torus will be four-dimensional. If a system consists of a
single hinged pendulum driven by a regular impulse, the pendulum will swing wildly and unpredictably, and the
attractor of the system will be a strange attractor. The attractor will be in a four-dimensional phase space, but it will
not be the Lorenz attractor illustrated in Figure 1, which is intended to illustrate a well-known strange attractor.
Because chaotic systems have strange attractors and sensitive dependence on initial conditions, any measurement
error made in measuring a chaotic system will be magnified by the dynamical processes of the system in such a way
that prediction of the future behavior of the system is essentially impossible (Kellert 1993). In any system with
sensitive dependence on initial conditions, an arbitrarily small error in measurement can result in a large difference
between the predicted behavior of the system and its actual behavior. Chaotic systems' strange attractors magnify
this property in such a way that arbitrarily precise measurements of the physical state of a chaotic system do not
determine where the system will be within its phase space after some period of time. This comes about because the
complex structure of the strange attractor within a particular basin of attraction makes it impossible to determine
where the system will be within the basin of attraction. Without measuring devices of infinite precision and the
ability to work with infinite precision measurements, it is impossible to measure or describe the state of a chaotic
system with enough precision to distinguish that state from distinct states that are nearby in the phase space. Thus,
there are no finite definitions of the high-level states of a chaotic system in terms of the low-level physical quantities
on which they supervene.
In "Quining Qualia," Daniel Dennett presents four characteristics of qualitative experiences:
(d) directly apprehensible. (Dennett 1988)
In presenting these characteristics, Dennett clearly intends to suggest that they are part of the reason why qualitative
experiences are difficult for physicalists to explain. While one can understand these characteristics in such a way
that no physicalistic explanation is possible, such an approach simply assumes that physicalism is false. To avoid
begging the question in this way, one must understand these characteristics in a way that is neutral with respect to
physicalism, and then ask if there is an explanation of these characteristics in physical terms. In what follows, I seek
to explain each of the characteristics mentioned by Dennett using chaos theory.
Consider first the idea that qualia are (a) ineffable. To say that something is ineffable is to say that it cannot be
known or described. Chaos theory demands that some unknowable or indescribable properties should exist in the
sense that there are properties of chaotic systems that cannot be finitely described. For example, predictive
properties about what a chaotic system will do cannot be finitely described because chaotic systems have sensitive
dependence on initial conditions and strange attractors (Kellert 1993). To know or describe these properties would
require the ability to measure the relevant system with infinite precision, and to compute with infinite precision.
Since this is impossible, the properties in question cannot be known or described.
There are two objections to this argument. First, it might be argued that something that is ineffable cannot be
described at all, not even in theory. Since the indescribable properties of a chaotic system could in theory be
described using infinite descriptions, one might think that this means no chaotic properties are ineffable. I think,
however, that this argument is contrary to the naturalism and physicalism that I have assumed. Let us assume that
something is ineffable if it cannot be known by any possible agent. Then this objection will stand if some possible
agent can make use of infinite descriptions. However, if a natural physical agent requires a finite non-zero amount of
matter to represent each binary digit of a description that it will use, then an agent that could make use of infinite
descriptions must be supernatural since the representational capacity of such an agent would require infinite matter,
and an infinite material agent is impossible. Consequently the objection does not stand.
Second, it might be argued that indescribable properties of a chaotic system can be described in a general way, and
that they are thus not ineffable after all. There are two common expressions for these general descriptions of chaotic
systems; the first refers to the 'order' that comes from the 'disorder' of a chaotic system, and the second refers to the
'qualitative' properties of the system. The kind of general properties involved can be illustrated using the Lorenz
Attractor, which has two easily noticed lobes. While one cannot describe the Lorenz attractor with sufficient
precision to predict the behavior of a system that is characterized by that attractor, one can say that the system will
have two modes of behavior with unpredictable transitions between them. But if this level of description contravenes
the ineffability of the chaotic properties, it contravenes the ineffability of qualitative experiences as well. We can
certainly note that our visual system, for example, has characteristic modes of behavior with unpredictable
transitions between them. This objection doesn't stand either, and I believe that it is possible to explain the
ineffability of qualitative experiences by appeal to the ineffability of some properties of chaotic systems.
To say that qualitative experiences are (b) intrinsic is to say that they are not defined relationally or functionally.
Intrinsic are basic in the sense that their defining characteristics are internal rather than external. They may play a
role in a functional organization, but their functional role is not their defining character. Some chaotic systems will
have states with characteristic features independent of any functional or relational properties. Some chaotic systems
will have several strange attractors within their phase space. Being in the basin of attraction of a particular strange
attractor is a state that is defined by the dynamical properties of a chaotic system. Such states are realized in
response to the system's environment, and at any time a change in the environment may move the system from one
basin of attraction to another. From a particular basin of attraction some basins of attraction will be more easily
reached than others either by virtue of being nearby in the phase space, or by virtue of requiring a smaller
environmental change to move the system from one basin of attraction to another. (To imagine this, think of a
marble in an egg carton. A shock to the egg carton can move the marble into an adjacent well. If the egg carton was
more irregularly shaped, the shock required to move the marble from one well to another would be different
depending on the height of the divider between the two wells.)
A chaotic system will move among the basins of attraction in its phase space in response to the environment, and
each basin of attraction may be interpreted as a functional state of the system since it will correspond to different
sets of dispositions to respond to the environment. However, these states are a consequence of the dynamics of the
system, and they have their own internal structure that is much finer-grained than the coarse functional structure of
which the basins of attraction are a part. The functional organization at the higher level could be modeled or
instantiated in other systems with a different fine-grained structure, or perhaps without any fine-grained structure at
all. The functional organization is a self-organized consequence of the dynamics of the system, as is the fine-grained
structure, but the functional organization does not define the fine-grained structure; both are consequences of the
dynamics of the system as a whole, and the functional organization could occur independently of the fine-grained
structure. Thus, being in the basin of attraction of a strange attractor has a kind of intrinsic character derived from
the fine-grained structure of the attractor, and this intrinsic character is distinct from the functional role that the basin
of attraction plays in the system. If the brain is a chaotic system, and if mental states correspond to strange attractors
as Freeman's research seems to suggest (Skarda and Freeman 1990), then we can use the intrinsic character of such
properties to explain the intrinsic nature of qualitative experience.
Due to the severe epistemological constraints on our knowledge of the strange attractors in a chaotic system, there is
a kind of (c) privacy that arises in such systems. These systems and their states cannot be described or
communicated finitely for reasons that have been discussed above in the discussion of the ineffability of these states.
No third-person descriptions of the state of such systems is adequate. At the same time, the states of such systems
can be known to the systems that have them in the sense that the states constitute the self-knowledge of the system.
The system includes feedback loops that allow the current state of the system to influence its future behavior. This
amounts to a kind of first-person point of view, or a kind of subjectivity. The states of a chaotic system are private in
that they are accessible only to the system of which they are a part, and not to any external observer. This constraint
seems to be as good a model for privacy in physical systems as one could hope for. If qualitative mental states
supervene on basins of attraction of strange attractors in the brain, we can explain why qualitative experiences are
private and can only be known 'from within.'
Dennett's fourth suggestion is that qualia are (d) directly or immediately apprehensible in consciousness. In
considering the notion of privacy, I have already alluded to how this property is to be explained. Each point in the
phase space of a chaotic system represents a possible total state of that system. When a chaotic system is within the
basin of attraction of a strange attractor, the system can know that this is the case because being in the basin of
attraction of that strange attractor is part of the total state of the system. Feedback loops or self-monitoring systems
of any kind will allow the future total state of the system to be influenced by the current state, and a system with
such loops may be said to 'represent' itself. Feedback loops are characteristic of chaotic systems. The total state and
the dynamics of a chaotic system govern the future behavior of the system, thus playing a causal role in any
behavior that might be interpreted as reporting the system's current state. Because the total state of the system plays
a causal role in the future behavior of the system, there is no question about whether or not the system has access to
any parts of the total state. Further, it is easy to apply this model to the human nervous system since we already
know that many parts of the central nervous system include feedback loops and other reciprocal connections. Direct
access is thus explained by feedback loops and their role in a chaotic system.
Though the matter is not yet settled, there is good evidence that human central nervous systems are chaotic in the
sense described above. There are a number of studies of human EEG recordings that indicate that the human brain is
chaotic (Basar 1990). There are also studies of the rabbit olfaction system which indicate that it is chaotic (Skarda
and Freeman 1990). Since rabbits and humans are both mammals with similar neural systems, chaos in rabbit neural
systems is evidence that human neural systems are chaotic as well.
If the four characteristics listed by Dennett are sufficient for qualitative experience, and if the proposed explanation
of these characteristics given above is correct, then it is possible to explain qualitative experiences in physicalistic
terms. Since Dennett's list of four characteristics is evidently intended to suggest why qualitative experiences are
difficult for physicalists to explain, I believe it is worthwhile to investigate whether or not human qualitative
experiences can be correlated to chaotic strange attractors in the phase space of the brain.
Basar, Erol. 1990. "Chaotic Dynamics and Resonance Phenomena in Brain Function: Progress, Perspectives, and
Thoughts". In Chaos in Brain Function, edited by E. Basar. Berlin: Springer-Verlag.
Dennett, Daniel C. 1988. "Quining Qualia". In Consciousness in Contemporary Science, edited by A. J. Marcel and
E. Bisiach. Oxford: Clarendon Press.
Devaney, Robert L. 1989. An Introduction to Chaotic Dynamical Systems. Edited by R. L. Devaney. Second Edition
ed, Addison Wesley Studies in Nonlinearity. Redwood City, California: Addison-Wesley Publishing Company, Inc.
Gleick, James. 1987. Chaos: Making a New Science. New York: Penguin Books.
Hilborn, Robert C. 1994. Chaos and Nonlinear Dynamics: An Introduction for Scientists and Engineers. Oxford:
Oxford University Press.
Kellert, Stephen H. 1993. In the Wake of Chaos: Unpredictable Order in Dynamical Systems. Edited by D. L. Hull,
Science and Its Conceptual Foundations. Chicago: The University of Chicago Press.
Skarda, Christine, A., and Walter J. Freeman. 1990. "Chaos and the New Science of the Brain." Concepts in
Neuroscience 1 (2):275-285.
Stewart, Ian. 1989. Does God Play Dice?: The Mathematics of Chaos. Cambridge, Massachusetts: Basil Blackwell
The mathematics of chaos describe systems with radically unpredictable and continually novel behavior(Kellert
1993). Chaotic systems' behavior is unpredictable by finite agents since such agents can only measure and calculate
with finite precision, and since chaotic systems' property of sensitive dependence on initial conditions makes it
necessary to measure them with infinite precision and calculate with infinite precision using those measurements in
order to predict their behavior. Chaotic systems thus have a kind of radical unpredictability similar to that which
Wiener must have desired in creative systems. Moreover, chaotic systems' behavior is novel in a mathematically
precise sense: it is not periodic, and thus it does not repeat itself. While Deep Blue probably isn't a chaotic system, it
is easy to see how Kasparov could find a short stretch of seemingly human behavior in its chess-playing since its
complexity undoubtedly is approaching that of chaotic systems.
Because neither consciousness nor matter is reducible to the other, they are distinct and different phenomena in the
world. Those who believe that consciousness is reducible to matter are called materialists; those who believe that
matter is reducible to consciousness are called idealists. Both are mistaken for the same reason. Both try to eliminate
something that really exists in its own right and cannot be reduced to something else. Now, because both
materialism and idealism are false, the only reasonable alternative is dualism. But substance dualism seems out of
the question for a number of reasons. For example it cannot explain how these spiritual substances came into
existence in the first place and it cannot explain how they relate to the physical world. So property dualism seems
the only reasonable view of the mind–body problem. Consciousness really exists, but it is not a separate substance
on its own, rather it is a property of the brain.
Making Sense of Causal Interactions Between Consciousness and Brain
Abstract: My target article (henceforth referred to as TA) presents evidence for causal interactions between
consciousness and brain and some standard ways of accounting for this evidence in clinical practice and
neuropsychological theory. I also point out some of the problems of understanding such causal interactions that are
not addressed by standard explanations. Most of the residual problems have to do with how to cross the ‘explanatory
gap’ from consciousness to brain. I then list some of the reasons why the route across this gap suggested by
physicalism won’t work, in spite of its current popularity in consciousness studies. My own suggested route across
the explanatory gap is more subterranean, where consciousness and brain can be seen to be dual aspects of a
unifying, psychophysical mind. Some of the steps on this deeper route still have to be filled in by empirical research.
But (as far as I can judge) there are no gaps that cannot be filled — just a different way of understanding
consciousness, mind, brain and their causal interaction, with some interesting consequences for our understanding of
free will. The commentaries on TA examined many aspects of my thesis viewed from both Western and Eastern
perspectives. This reply focuses on how dual-aspect monism compares with currently popular alternatives such as
‘nonreductive physicalism’, clarifies my own approach, and reconsiders how well this addresses the ‘hard’ problems
of consciousness. We re-examine how conscious experiences relate to their physical/functional correlates and
whether useful analogies can be drawn with other, physical relationships that appear to have dual-aspects. We also
examine some fundamental differences between Western and Eastern thought about whether the existence of the
physical world or the existence of consciousness can be taken for granted (with consequential differences about
which of these is ‘hard’ to understand). I then suggest a form of dual-aspect Reflexive Monism that might provide a
path between these ancient intellectual traditions that is consistent with science and with common sense.
How Could Conscious Experiences Affect Brains?
In everyday life we take it for granted that we have conscious control of some of our actions and that the part of us
that exercises control is the conscious mind. Psychosomatic medicine also assumes that the conscious mind can
affect body states, and this is supported by evidence that the use of imagery, hypnosis, biofeedback and other
‘mental interventions’ can be therapeutic in a variety of medical conditions. However, there is no accepted theory of
mind/body interaction and this has had a detrimental effect on the acceptance of mental causation in science,
philosophy and in many areas of clinical practice. Biomedical accounts typically translate the effects of mind into
the effects of brain functioning, for example, explaining mind/body interactions in terms of the interconnections and
reciprocal control of cortical, neuroendocrine, autonomic and immune systems. While such accounts are instructive,
they are implicitly reductionist, and beg the question of how conscious experiences could have bodily effects. On
the other hand, non-reductionist accounts have to cope with three problems: (1) The physical world appears causally
closed, which would seem to leave no room for conscious intervention. (2) One is not conscious of one’s own
brain/body processing, so how could there be conscious control of such processing? (3) Conscious experiences
appear to come too late to causally affect the processes to which they most obviously relate. This paper suggests a
way of understanding mental causation that resolves these problems. It also suggests that ‘conscious mental control’
needs to be partly understood in terms of the voluntary operations of the preconscious mind, and that this allows an
account of biological determinism that is compatible with experienced free will.
Amplifying Phenomenal Information. Toward a Fundamental Theory of Consciousness
Abstract: Fundamental approaches bypass the problem of getting consciousness from non-conscious components by
positing that consciousness is a universal primitive. For example, the double aspect theory of information holds that
information has a phenomenal aspect. How then do you get from phenomenal information to human consciousness?
This paper proposes that an entity is conscious to the extent it amplifies information, first by trapping and integrating
it through closure, and second by maintaining dynamics at the edge of chaos through simultaneous processes of
divergence and convergence. The origin of life through autocatalytic closure, and the origin of an interconnected
worldview through conceptual closure, induced phase transitions in the degree to which information, and thus
consciousness, is locally amplified. Divergence and convergence of cognitive information may involve phenomena
observed in light e.g. focusing, interference, and resonance. By making information flow inward- biased, closure
shields us from external consciousness; thus the paucity of consciousness may be an illusion.
Correspondence: Liane Gabora, Center Leo Apostel for Interdisciplinary Studies (CLEA),
Free University of Brussels (VUB), Krijgskundestraat 33, Brussels, B1160, Belgium.